[c-nsp] Forecasting

[Mark Borchers]

> 	Hi, folks. I've used a variety of network management tools, both
> commercial and open sourced. So far, I've only come across 
> one that graphs
> trend lines for utilization for forecasting, and this is with Lucent's
> Vitalsuite.
> 
> 	Is anyone else aware of any other tools, preferably 
> open sourced,
> that can graph trend lines to anticipate usage 3-6 months out? 
> 
> 	Apparently, RRDTool/Cricket fully supports the Holt-Winters
> algorithm, which can be configured to display the confidence 
> bands to report
> on aberrant data, but the time scale is still based on actual usage.

The last time I checked, Vitalsuite appeared to be a straight linear
extrapolation of current traffic measurements into the future.  Classic
GIGO, with wild variations in future trends showing up as a result of
the September effect and so forth.

IMHO, the bad news is that if you want a judicious projection, you
have to go into a spreadsheet with some educated guesses about expected
changes in bandwidth utilization per user, subscriber growth,
datacenter-
specific trends, and the like in order to get a more refined number for
capacity planning.